The authors systematically studied the introduction of animal-assisted activity into a children's hospital in Italy. This pilot study examined the reactions of children, their parents and the hospital staff and the hospital-wide infection rate before and after the introduction of animals. The SAM (self-assessment manikin), three behavioral scales, analysis of children's graphic productions, a parent questionnaire and a staff questionnaire were used to evaluate the effectiveness of the intervention. The children's participation was calculated. The analysis of the hospital infection rate was completed independently by the Hospital Infections Committee. The authors found that the presence of infections in the wards did not increase and the number of children at the meetings with pets in the wards was high (138 children). The study also found that the presence of animals produced some beneficial effects on children: a better perception of the environment and a good interaction with dogs. All parents were in favor of pets in the hospital, and 94% thought that this activity could benefit the child, as did the medical staff, although the staff needed more information about safety. The introduction of pets into the pediatric wards in an Italian children's hospital was a positive event because of the participation of hospitalized patients, the satisfaction expressed by both parents and medical staff, and the fact that the hospital infection rate did not change and no new infections developed after the introduction of dogs.